Shock wave studies of the pyrolysis of fluorocarbon oxygenates. II. The thermal dissociation of C4F8O

Abstract

The thermal decomposition of octafluorooxalane, C₄F₈O, to C₂F₄ + CF₂ + COF₂ has been studied in shock waves highly diluted in Ar between 1300 and 2200 K. The primary dissociation was shown to be followed by secondary dissociation of C₂F₄ and dimerization of CF₂. The primary dissociation was found to be in its falloff range and falloff curves were constructed. The limiting low and high pressure rate constants were estimated and compared with modelling results. Quantum-chemical calculations identified possible reaction pathways, either leading directly to the final products of the reaction or passing through an open-chain CF₂CF₂CF₂ intermediate which dissociates in a second step.